Method and apparatus for sampling liquid

ABSTRACT

The present invention provides a method and apparatus for wastewater sampling in all climates. The wastewater sampling apparatus pulls a sample from a stream or other body of water based on flow or time maintaining a consistent, repeatable, and accurate sample size. The present invention includes an all-weather housing. An integrated touchscreen control provides the ability to specify the volumes of water and program times and/or flow intervals to collect samples. Controls also allow control of the temperature within the sample compartment, both from the unit directly or from an external device. The present invention includes arcuate sample chamber and pivoting sample tube for accurate wastewater volume samples. The present invention may pull samples with vertical lifts of up to 29 feet or more and provide consistent accurate sampling exceeding current EPA transport velocity.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 16/902,113,filed on Jun. 15, 2020, entitled METHOD AND APPARATUS FOR SAMPLINGLIQUID, which is a nonprovisional of application Ser. No. 62/861,437,filed Jun. 14, 2019, entitled METHOD AND APPARATUS FOR SAMPLING LIQUID.

FIELD

The present invention relates to a method and apparatus for samplingliquid and, more particularly, a method and apparatus for samplingwastewater with a programmable liquid sampler which utilizes anadjustable effective height of the intake tube to vary the sample size.

BACKGROUND

Vacuum liquid samplers are generally known in the art. Some automaticliquid samplers use a load cell to measure the sample weight. Thismeasured weight is then used in an adaptive feedback loop to improvefuture sample size control. This technique is costly because load cellsare expensive, mechanically fragile and require expensive signalconditioning electronics, resulting in an unreliable system.

A lower cost alternative is to fix the sample size by manually adjustingan intake tube up and down to vary the sample size. Vacuum is applied tothe sample chamber via the vacuum/pressure port to draw the sample intothe sample chamber via the suction tube until the chamber is overfilled.Pressure is then applied to the sample chamber, and the excess sample isdischarged back out through the suction line until the sampling level iseven with the bottom rim of the suction tube. At this point no moresample will be discharged. A valve on the discharge line is then openedand the sample is expelled from the sample chamber. This samplingtechnique is reliable and repeatable, but it is very difficult toadjust. Furthermore, not limiting the amount of initial oversampleaffects the quality of the sample. A reliable and repeatable samplingmethod and apparatus is desired.

SUMMARY

Embodiments of the invention are defined by the claims below, not thissummary. A high-level overview of various aspects of the invention areprovided here for that reason, to provide an overview of the disclosure,and to introduce a selection of concepts that are further described inthe Detailed Description section below. This summary is not intended toidentify key features or essential features of the claimed subjectmatter, nor is it intended to be used as an aid in isolation todetermine the scope of the claimed subject matter. In brief, thisdisclosure describes, among other things, methods, systems, andapparatus for liquid sampling utilizing precise adjustment control toadjust the effective height of the suction tube within the samplechamber with feedback to limit the amount of oversample.

The present invention includes a method and apparatus for wastewatersampling in all climates. The wastewater sampling apparatus includes arefrigeration/heater unit to maintain the temperature of the sample to arange of +/−10 to 2 degrees C. in most climates. The wastewater samplingapparatus may pull a sample from a stream or other body of water basedon flow, time, or combinations of flow and time, as desired by theoperator, maintaining a consistent, repeatable, and accurate samplesize.

The present invention provides an electronically controlled, heavy dutyvacuum wastewater sampler. A refrigerated sampler allows for bothcomposite and sequential sampling options with a high level of accuracy.The present invention includes an all-weather housing, making thisall-season unit perfect for even the harshest of outdoor and indoorenvironments. An integrated touchscreen controls provides the ability tospecify the volumes of water and program times and/or flow intervals tocollect samples. Controls also allow control of the temperature withinthe sample compartment, both from the unit directly or from an externaldevice. The present invention includes a powerful vacuum system togenerate stronger purges to remove contamination and draw samples fromgreater distances. The present invention may pull samples with verticallifts up to 29 feet or more and provide consistent accurate samplingexceeding current EPA transport velocity requirements.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of the housing for the apparatus for samplingliquid of the present invention.

FIG. 2 is a rear view of the housing of FIG. 1 .

FIG. 3 is a side view of the housing of FIG. 1 .

FIG. 4 is a perspective view of the major components of the apparatusfor sampling liquid of the present invention.

FIG. 5 is an enlarged partial view of the stepper motor and drive gear.

FIG. 6 is a view of the interior of the sample chamber.

FIG. 7 is another view of the interior of the sample chamber with thesampling tube shown in another position.

FIG. 8 is an enlarged partial view of a balancing sampling apparatus ofthe apparatus for sampling liquid of the present invention.

FIG. 9 is an enlarged partial view of a pinch valve assembly of theapparatus for sampling liquid of the present invention.

FIG. 10 is a view of the pinch valve assembly of FIG. 9 viewed frombelow.

FIG. 11 is an internal view of the pinch valve assembly of FIG. 9 .

FIG. 12 is a schematic of the control unit for the apparatus of thepresent invention.

FIG. 13 is a chart showing the relationship between the position of thesampling tube and sample size using a least-squares method ofregression.

FIG. 14 is another chart showing the relationship between the positionof the sampling tube and sample size using a higher order polynomialbest fit regression.

FIGS. 15-38 are sample setting screens of the present invention.

FIGS. 39-61 are interval setting screens of the present invention.

FIGS. 62-73 are bottle setting screens of the present invention.

FIGS. 74-99 are advanced screens of the present invention.

FIGS. 100-146 are program settings screens of the present invention.

DETAILED DESCRIPTION

The subject matter of select embodiments of the invention is describedwith specificity herein to meet statutory requirements. But thedescription itself is not intended to necessarily limit the scope ofclaims. Rather, the claimed subject matter might be embodied in otherways to include different components, steps, or combinations thereofsimilar to the ones described in this document, in conjunction withother present or future technologies. Terms should not be interpreted asimplying any particular order among or between various steps hereindisclosed unless and except when the order of individual steps isexplicitly described.

Referring initially to FIGS. 1-12 , an apparatus for sampling wastewateris generally indicated by reference numeral 20. The wastewater samplingapparatus 20 is mounted in a housing 22, and includes a sample chamber24, a sampling tube position controller 26, a sample balance 28, a pinchvalve assembly 30, a vacuum pump 32, a refrigeration unit 34, and asystem controller 36.

The sample chamber 24 includes a sampling tube 38 pivotally mountedwithin the sample chamber 24, a vacuum/pressure port 40, and a drain 42.The sampling tube 38 includes an inlet 44 and an outlet 46. The samplechamber 24 is generally a wedge of a spherical segment with an arcuateouter wall 48 equidistant from the inlet 44 of the sampling tube 38 asthe sampling tube 38 rotates about an axis 50. Selection of thevacuum/pressure is controlled by the vacuum/pressure solenoid 37 coupledto the controller 36.

The angular position of the sampling tube 38 is controlled by thesampling tube position controller 26. The sampling tube positioncontroller 26 includes a drive motor 52, which is coupled to the systemcontroller 36. In the preferred embodiment, the drive motor 52 is astepper motor for precise control and position of the sampling tube 38.

The system controller 36 includes a cooperative group of self-containedelectronic modules (FIG. 12 ). These modules provide both hardwaremodularity and software modularity. The present embodiment is comprisedof 1) a battery-backed embedded Linux computer, 2) a custom I/Ocontroller controlled by an ARM Cortex M4 controller cooperativelyconnected to various custom designed I/O circuits, and 3) a customrefrigeration controller designed to measure temperature and perform thebasic refrigeration controls. The embedded Linux computer communicateswith the I/O controller and the refrigeration controller via thephysical layer of a CAN bus interface. Each piece of hardware performsspecific control functions.

The embedded Linux computer performs high-level functions such as 1) afully graphical touchscreen user interface 100, 2) storing andretrieving all user configuration files, 3) performing real-timescheduling of the sampling events, 4) archiving and reporting samplingand exception information, 5) diagnostics, and 6) all externalcommunications.

The I/O board contains its own microcontroller which interprets commandsfrom the embedded Linux computer and then performs a single samplecompletely under self-control. This prevents non-deterministic behaviorof Linux from corrupting the sampling process. Also, activities likeflow monitoring and alarm generation are controlled via the I/O board.The I/O board also fully implements its own stepper motor controller forhighly deterministic positioning of the sampling tube. The pinch-valveis controlled via an internal state machine within the I/O board.

The refrigeration control is a self-contained refrigeration controlwhich keeps the cabinet temperature within preset limits. Itcommunicates cabinet conditions to the embedded Linux controller.

Each hardware module incorporates its own software or firmware. Both theI/O board and the refrigeration control are programmed in C++ andutilize an open-source framework.

The embedded Linux microprocessor uses a variety of software modules toperform its functions. The User interface is written as a stand-aloneprocess which communicates to a backend process via a REST API. Thisprovides for an architecture which can support additional interfaces inthe future. For example, a sampler can be controlled via a secure website, or a mobile device can be redirected to interface to multiplesamplers.

The backend process exposes a REST API interface, but also performs allscheduling, control and archiving functions. Time-critical functions,such as the CAN bus interface are forked as separate processes toleverage the multi-core architecture of the microprocessor. The embeddedLinux computer can be easily connected to the Internet for remotediagnostics, calibration and control via Secure Shell protocol (SSH) orother known protocols.

The SSH protocol may be used to provide secure access for users andautomated processes, interactive and automated file transfers, issuingremote commands, and managing network infrastructure and othermission-critical system components. The embedded Linux control alsoincorporates a companion battery backup module which monitors for powerloss and provides for an orderly shutdown and reboot as necessary. Thisprevents power fluctuations from damaging the Linux file system. Thebattery backup module also performs real-time clock functions so theLinux system can maintain a consistent time-base independent of theInternet.

The drive motor 52 is mounted above the sample chamber 24. A drive gear54 is mounted to a drive shaft 56 of the drive motor 52, which iscoupled to a driven gear 58 mounted directly to the outlet 46 of thesampling tube 38. In the preferred embodiment, the drive motor 52 is astepper motor and the position of the sampling tube 38 is controlled bycounting the steps of the stepper motor 52. The positional limits of thesampling tube 38 may also be controlled by a limit switch 60, which isused for homing.

The sample balance 28 includes a balance plate 62. The sample chamber 24and sampling tube position controller 26 are mounted to the balanceplate 62 of the sample balance 28. The balance plate 62 balances at afulcrum 64 which is rigidly mounted to the cabinet chassis 66. Thecenter of mass of the sample chamber 24 is in front 68 of the fulcrum64. The balance plate 62 includes adjustment apertures 70 to balance thesample chamber 24, sampling tube position and sample balance 28. Thebalance plate 62 may be positioned relative to the fulcrum 64 such thatwhen the sample chamber 24 is empty, there may be slightly more mass infront 68 of the fulcrum 64 than behind 72 the fulcrum 64 resulting in aslight downward pressure at the front 74 of the balance plate 62. Thefront 74 of the balance plate 62 includes a cylindrical forceconcentrator 76 resting on top of a force sensor 78. The force sensor 78may be a force sensing resistor, a load cell, a strain gauge, or otherpressure sensor. The output of the force sensor 78 is coupled to thesystem controller 36, which linearizes the output as a function offorce.

The system controller 36 positions the sampling tube 38 within thesample chamber 24 for a desired sample volume. The system controller 36energizes the vacuum/pressure solenoid 37 to apply a vacuum to thevacuum/pressure port 40 of the sample chamber 24. Wastewater is drawninto the inlet 44 and out through the outlet 46 of the sampling tube 38into the sample chamber 24. The output of the sample balance 28 iscalibrated to slightly oversample the wastewater for a desired samplevolume. When the volume of the wastewater exceeds the desired volume(weight), the system controller 36 energized the vacuum/pressuresolenoid 37 to apply pressure to the vacuum/pressure port 40 of thesample chamber 24. A volume of oversampled wastewater is forced back outthe outlet 46 through the inlet 44 until the level of the wastewatersample in the sample chamber 24 is below the rim of the outlet 46,resulting in a precise wastewater sample volume. In this manner, solidsin the wastewater stream may also be discharged. When the desiredwastewater volume is contained in the sample chamber 24, the pinch valve80 is opened and the wastewater flows through the drain 42 and tube 84to the collection bottle.

Other methods may be used to limit the amount of oversample in a samplecycle such as an external array of capacitance sensors on an exteriorwall of the sample chamber 24. The capacitance sensors may signal whento terminate the suction cycle and initiate the pressure cycle. By usingmultiple capacitive sensor pairs in proximity to the sample chamber, thecontrol microprocessor may be signaled to terminate the vacuum cycle atone of a multiple of distinct levels. Alternatively, a single linearcapacitive sensing pair may be used for continuously monitoring levels.Discrete pairs may be preferable for simplicity and noise immunity.

The pinch valve assembly 30 serves to retain liquid within the samplechamber 24, then release the fluid when sampling is completed. The pinchvalve assembly 30 includes a housing 80 mounted to a bracket 82, whichis coupled to the balance plate 62. The pinch valve assembly 30 issuspended below the sample chamber 24, in alignment with a drain tube 84coupled to the drain 42 without contacting any other component withinthe enclosure. A pinch valve assembly 86 is mounted in the housing 80and includes a rotating eccentric cam 88, a floating pinch rod 90 and alimit switch 92. A drive motor 94 is mounted to the bracket 82 andincludes a drive shaft 96 coupled to the rotating eccentric cam 88. Thedrain tube 84 is composed of a relatively soft flexible material such asvinyl, rubber or silicone, that is easily compressed to create a tightseal to prevent any flow through the tube 84, and readily springs backto its original shape when not compressed. As the drive motor 94 rotatesthe eccentric cam 88, the pinch rod 90 is pressed against the drain tube84 withing the housing 80 to stop fluid flow through the drain tube 84from the sample chamber 24. The limit switch 92 is activated by theeccentric cam 88 for positional feedback. As the drive motor 94 rotatesthe eccentric cam 88 to open the pinch valve, the pinch rod 90 istranslated away from the drain tube 84, which returns to its originalshape allowing fluid to flow through the drain tube 84 from the samplechamber 24.

The user interface 100 is a touch screen that provides information andfeedback to the user. The home screen is the main screen viewed on startup. The home screen allows easy access to program information and thestatus of the current running program and its settings under it.

Referring to FIGS. 13 and 14 , software calibration of sample size maybe varied by changing the angle of the sampling tube 38 relative to thesample chamber 24. The larger deflection from vertical, the larger thesample size. Since the deflection from vertical is performed via astepper motor 52, a mathematical relationship may be determined linkingsteps as a function of sample size in milliliters. Because of the shapeof the container 24, and because the depth of the sample in thecontainer is a function of the cosine of the deflection angle, thefunction relating sample size to steps is highly non-linear.Consequently, there is a need for each chamber and sampling tubeassembly to be software calibrated. For small sample sizes, many stepshave a very small impact on size, but for large sample sizes only a fewsteps can be significant. However, the chamber is designed such that thefunction relating the logarithm of sample size to steps is quite linear.Thus, a relationship for steps as a function of sample size can beestablished for each container and sampling tube assembly by using aleast-squares method of regression (see for example, FIG. 13 ).

Another embodiment may be realized by using a higher order polynomialbest fit regression method (FIG. 14 ). A preferred embodiment isrealized by combining these techniques to allow a search algorithm tofind a specific set of (log(ml), step) pairs. For example, multiplesamples can be taken to determine the precise steps to produce 20, 50,100, 200, 300, 400 and 500 ml sample sizes. A smooth function may bedetermined by using mathematical spline functions to join the (log(ml),steps) pairs. This minimizes errors on popular sample sizes and acceptssmall errors between those sizes. Further refinements in softwarecalibration can be envisioned.

Referring to FIGS. 15-38 , configuration of the sampling program isindicated. To customize a sampling program, the home screen initiallydisplays “IDLE PROGRAM”. Selection of the configuration icon 104 on theleft side of the screen advances the system to an “EXISTING PROGRAMS”screen (FIG. 15 ). To change or create a program, either “Program 1” or“NEW” may be selected (FIG. 16 ). When “Program1” or “NEW” is selected,the screen changes to allow access and change four settings of theprogram: “SAMPLING, INTERVAL, BOTTLE, & ADVANCED” (FIG. 16 ). To build anew program, “NEW” is selected, the same screen will be displayed butwith the “NEW” button highlighted. To continue making changes orbuilding a new program one of the aforementioned settings may beselected. All “Settings” may be accessed and changed from the samescreen.

To change the settings of a program, the “SAMPLING” button may beselected, which turns is highlighted and the “EDIT” button is displayed(FIG. 17 ). Selection of the “EDIT” button to displays the settings ofthe sampling parameters (FIG. 18 ). The Sampling settings include:Rinses, Rinse Purge, Rinse Suction, Pre-Purge, Sample Size, SampleSuction, Post Purge, Retries and Samples Group (FIG. 18 ).

The Rinses setting is the number of times the sampler will rinse thesample line prior to pulling each sample. The rinse cycle will purge thesample line then pull liquid up the sample line, but not into the samplechamber. This may be done a number of times. Pressing the “Rinses”button displays the numeric entry keys used to enter the number ofrinses in the window (FIG. 19 ). A numeric value from 1-4, for example,may be entered to rinse the sample line prior to pulling the actualsample. To skip rinsing the line first, 0 may be entered. When 0 isselected the Rinse Purge and Rinse Suction settings may be grayed out.Entering a numeric value will activate the Rinse Purge and Rinse Suctionsettings and they will no longer be grayed out.

After entering a value and selecting Save, and “Updated Successfully”will appear in the lower right-hand corner if the value is accepted(FIG. 20 ). Other settings may be changed or added under the SamplingSettings by selecting and saving the entries.

The Rinse Purge setting is the amount of time it takes to purge thesample line prior to pulling the rinse liquid into it (FIG. 21 ). Therange of time may be set from 0.1 to 45.0 seconds. Selecting “RinsePurge” button displays the numeric entry keys to enter the amount oftime in the window under “SETTINGS”. After entering the amount of timeto purge the line, press Save, and “Updated Successfully” will appear inthe lower right-hand corner if the time is accepted (FIG. 22 ).

The Rinse Suction setting is the amount of Vacuum Time needed to pullthe rinse liquid up to the sampler, but preferably not into it.Selecting the “Rinse Suction” button provides access to the numericentry keys used to enter the amount of time in the window under“SETTINGS” (FIG. 23 ). After entering the amount of Vacuum time to rinsethe line, press Save, and “Updated Successfully” will appear in thelower right-hand corner if the value is accepted (FIG. 24 ).

The Pre-Purge setting is the amount of time to purge the sampleline/suction strainer prior to pulling the sample. Selecting the“Pre-Purge” button provides access to the numeric entry keys used toenter the amount of time in the window under “SETTINGS” (FIG. 25 ). Theamount of time allowed is from 0.1-99.0 seconds. Purging the sample linebefore the sample is taken is preferred to achieve a represented sample.After entering an amount of time and selecting Save, “UpdatedSuccessfully” will appear in the lower right-hand corner if the value isaccepted (FIG. 26 ).

The Sample Size setting is the volume of sample to be measured and addedto the sample container (FIG. 27 ). Selecting the “Sample Size” buttonprovides access to the numeric entry keys used to enter the size ofrinses in the window under “SETTINGS”, in the range from 20-500 ml.After entering the desired Sample Size, press Save, and “UpdatedSuccessfully” appears in the lower right-hand corner if the value isaccepted (FIG. 28 ).

The Sample Suction setting is the amount of Vacuum Time needed to pullthe desired sample into the sample chamber for collection (FIG. 29 ).Selecting the “Sample Suction” button provides access to the numericentry keys used to enter the amount of time in the window under“SETTINGS”. The amount of time may be entered from 0.1-150 seconds.After entering the time, press Save, and “Updated Successfully” willappear in the lower right-hand corner if the value is accepted (FIG. 30).

The Post Purge setting is the amount of time needed to clean the lineout after the sample has been taken (FIG. 31 ). Select “Post Purge” toaccess the numeric entry keys used to enter the amount of time in thewindow under “SETTINGS”. The range is from 10-200 seconds. Afterentering the time press Save, and “Updated Successfully” will appear inthe lower right-hand corner if the value is accepted (FIG. 32 ).

The Retries setting is the number of times the sampler will try toretake a sample if it fails to do so the first time (FIG. 33 ). Thiscould be caused from the suction line being out of the water or notenough suction time or a partially plugged suction line. Selection ofthe “Retries” button provides to access the numeric entry keys used toenter the number of times in the window under “SETTINGS”. The range maybe from 0-4 or more times, for example. If zero is selected the settingis turned off. After entering the number of Retry times and pressingSave, the “Updated Successfully” will appear in the lower righthandcorner if the value is accepted (FIG. 34 ).

The Samples Group setting gives you the ability to collect sampleslarger than 500 ml (FIG. 35 ). By increasing the Sample group, thenumber of times the sampler is pulled will be repeated. For example, topull 750 ml per sample, the sample size may be set to 250 and the SampleGroups set to 3. Press the “Samples Group” button to access the numericentry keys used to enter the number of samples in the window under“SETTINGS”. The range may be from 1-24, for example. After entering thenumeric value press Save, and “Updated Successfully” will appear in thelower right-hand corner if the value is accepted (FIG. 36 ).

If more program changes are needed after you have saved your changes,press the “BACK” button to take you back to the “EXISTING PROGRAMS”screen. Then select the next item requiring changes such as Interval,Bottle, or Advanced (FIG. 37 ). If all the program changes are complete,press the Home icon to view and verify the selections under theirrespective TAB. If all selections are correct press the “RUN” buttonwhen ready to sample. Any time the programming is complete press theHome icon to return to the Home screen (FIG. 38 ).

The “INTERVAL” settings allow changes to the how the sample will betaken, such as Time, Max Flow, Flow Pulses, Flow 4-20, Link Bottle,Random Samples, Random Program, Random Min, Sample on Start, andExternal Input, for example.

From the “EXISTING PROGRAMS” screen press the “INTERVAL” button and the“EDIT” button will appear on the screen (FIG. 39 ). Press the “EDIT”button to access to the INTERVAL settings screen (FIG. 40 ). On the mainINTERVAL settings screen, choose from the settings listed above orselect the “BACK” button to go to the previous screen. All “Settings”may be accessed and changed from the same screen. Just press the nextbutton you want to make changes in.

The Time setting is the interval of time that you want to have betweeneach sample or how often you want the sample to be pulled (FIG. 41 ).Press the “Time” button to access the numeric entry keys used to enterthe time in the window under “SETTINGS”. The Time interval range is from4-9999 minutes in between each sample, for example. After entering thetime, press Save, and “Updated Successfully” will appear in the lowerright-hand corner if the value is accepted (FIG. 42 ).

The Max Flow setting is based on Gallons Per Minute (GPM). The GPM isthe maximum flow of the flowmeter scaling (FIG. 43 ). For example, if aflowmeter range is from 4-20, which equals 4 mA=0 GPM and 20 mA equals695 GPM (1 Million gallons per day), then would be entered 695 in thenumeric entry window. The sampler will determine the flow based on thesample information provided. Press the “Max Flow” button to access thenumeric entry keys used to enter the size of sample in the window under“SETTINGS”. Enter the Maximum Flow in GPM that the flowmeter mA signalrepresents. After entering the Maximum Flow, press Save, and “UpdatedSuccessfully” will appear in the lower right-hand corner if the value isaccepted (FIG. 44 ).

The Flow Pulses setting is the number of pulses to receive before thesampler pulls a sample (FIG. 45 ). For example, if the flowmeterproduces a pulse every 1,000 gallons and a sample is desired every 5,000gallons, 5,000÷1,000=5 flow pulses. Press the “Flow Pulses” button toaccess the numeric entry keys used to enter the number of pulses in thewindow under “SETTINGS”. After entering the numeric value, press Save,and “Updated Successfully” will appear in the lower right-hand corner ifthe value is accepted (FIG. 46 ).

The Flow 4-20 setting is used to set the sample rate in gallons betweensamples (FIG. 47 ). This setting is used in conjunction with Max Flowabove. Enter the gallons between samples. For example, to take a sampleevery 2500 gallons based on flow, enter 2500. Press the “Flow 4-20”button to access the numeric entry keys used to enter the rate in thewindow under “SETTINGS”. The range is from 4-20, for example. Afterentering the numeric value, press Save, and “Updated Successfully” willappear in the lower right-hand corner if the value is accepted (FIG. 48).

The Link Bottle setting allows linking bottles from different samples(FIG. 49 ).

The Random Samples setting allows the sampler to pull a specific numberof samples at random times within a set time (FIG. 50 ). This settingallows setting of the number of Random Samples to take, the time frame(Random Program) and the minimum amount of time (Random Min) betweeneach sample. Press the “Random Samples” button to access the numericentry keys used to enter the number of samples in the window under“SETTINGS”. The Random Samples range from 0-99 samples. After enteringthe number of samples, press Save, and “Updated Successfully” willappear in the lower right-hand corner if the value is accepted (FIG. 51).

The Random Program setting is the time frame the sampler is set to pullthe number of samples set in the Random Samples step above (FIG. 52 ).Press the “Random Program” button to access the numeric entry keys usedto enter the time in the window under “SETTINGS”. The Random Programrange is from 0-9999 minutes. Enter the amount of time for the samplerto pull the samples. After entering the time value, press Save, and“Updated Successfully” will appear in the lower right-hand corner if thevalue is accepted (FIG. 53 ).

The Random Min setting is the minimum time between samples the samplerwill use based on the number of samples set in the Random Samplessetting and within the time set in the Random Program setting (FIG. 54). Press the “Random Min” button to access the numeric entry keys usedto enter the time in the window under “SETTINGS”. The Random Min rangeis from 10-9999 minutes. Enter the time the sampler will pause betweensamples. After entering the minimum time between samples value, pressSave, and “Updated Successfully” will appear in the lower right-handcorner if the value is accepted (FIG. 55 ).

The Sample on Start setting allows the choice, if desired to take asample first when starting the program or based on the program time offlow (FIG. 56 ). When a program is started with this setting ON, itpulls a sample immediately providing immediate feedback (FIG. 57 ).

The External Input setting allows for an immediate sample to be takenoutside of the sample parameters (FIG. 58 ). Every time the contact isclosed a sample is taken. Press the “External Input” button to accessthe entry window. If this setting is OFF (under “SETTINGS”) the buttonwill be white with the words OFF. If this setting is ON, the button willbe Green with the words ON. Select the desired setting ON or OFF. Afterselecting ON/OFF per your preference, press Save, and “UpdatedSuccessfully” will appear in the lower right-hand corner if the value isaccepted (FIG. 59 ).

If more program changes are needed after you have saved your changes,press the “BACK” button to display the “EXISTING PROGRAMS” screen (FIG.60 ). If all the program changes are complete, press the Home icon toview and verify your selections under their respective TAB. If allselections are correct press the “RUN” button when ready to sample (FIG.61 ). Any time the programming is complete press the Home icon to returnto the Home screen.

The “BOTTLE” settings define the information about a sample bottle. Fromthe “EXISTING PROGRAMS” screen press the “BOTTLE” button and the “EDIT”button will appear on the screen (FIG. 62 ). Press the “EDIT” button toaccess to the BOTTLE functions screen (FIG. 63 ). All “Settings” may beaccessed and changed from the same screen.

Press the “Bottle Type” button to display the options of single andmultiple bottles under “SETTINGS” (FIG. 63 ). Open the pulldown windowby pressing the down arrow on the right side of the box. This pulldownwindow will show single bottle or multiple bottles. Select single bottle(FIG. 64 ). After selecting “single bottle”, press Save, and “UpdatedSuccessfully” will appear in the lower right-hand corner if the value isaccepted.

The Size setting button allows the bottle size to be changed for thecurrent program. Press the “Size” button to display the options ofbottle sizes under “SETTINGS” (FIG. 66 ). The pulldown window may beopened by pressing the down arrow on the right side of the box. Thispulldown window will show a bottle size such as 2.5 gallon or 5.0gallon, for example. Select the desired Bottle size. After selecting thebottle size, press Save, and “Updated Successfully” will appear in thelower right-hand corner if the value is accepted (FIGS. 67 and 68 ).

Samples Per Bottle setting is the number of samples that are needed tofill a 2.5 or 5-gallon bottle, for example. Press the “Samples perBottle” button to access the numeric entry keys used to enter thesamples per bottle in the window under “SETTINGS” (FIG. 69 ). Enter thenumber of Samples Per Bottle for this program. After entering the numberof samples per bottle, press Save, and “Updated Successfully” willappear in the lower right-hand corner if the value is accepted (FIGS. 69and 70 ).

The Full on External Input setting is used with the Full Bottle FloatSwitch. The float switch mounts in the lid of a bottle. If the bottlebecomes too full, it will trigger the float switch and shut the samplingprogram off to prevent a spill inside the sampler. When the container isemptied the program will start running again. Press the “Full onExternal Input” button to display the options of ON or OFF under“SETTINGS” (FIG. 71 ). The window will show ON or OFF. Select thedesired setting ON or OFF. After selecting ON/OFF per your preference,press Save, and “Updated Successfully” will appear in the lowerright-hand corner if the value is accepted (FIG. 72 ).

If more program changes are desired after saving the changes, press the“BACK” button to return to the “EXISTING PROGRAMS” screen, then selectthe next item requiring changes.

If all the program changes are complete, press the Home icon to view andverify selections under their respective TAB. If all selections arecorrect press the “RUN” button when ready to sample (FIG. 73 ). Any timethe programming is complete press the Home icon to return to the Homescreen.

The ADVANCED settings allow you to set up the Menu items (FIG. 74 ).

From the “EXISTING PROGRAMS” screen press the “ADVANCED” button and the“EDIT” button will appear on the screen. Press the “EDIT” button toaccess the ADVANCED settings screen (FIG. 75 ). All “Settings” may beaccessed and changed from the same screen.

The Start Time setting allows for programming a specific amount of timedelay before the program starts running (FIG. 76 ). For example, if thecurrent time is 8:00 am and it is desired to start sampling at 12:00p.m., 240 minutes would be entered (4×60=240) into the program linewindow (FIG. 77 ). Press the “Start Time” button to access the numericentry keys used to enter the time in the window under “SETTINGS”.

To run a Time or Flow based sample program with NO “Start Time” delay,set the value to “0” (FIG. 78 ). This will make the program startcounting immediately. Enter the time value, and press Save, and “UpdatedSuccessfully” will appear in the lower right if the value is accepted.

For example, if the programing is set to pull a sample every 10 minutesand it should start counting the 10 minutes down immediately, set “Time”under the Intervals settings to 10 and the “Start Time” to “0”. Verifythat the program is running correctly by pushing the program run FIG. 79).

Press the Home icon then Run, the screen will advance from IDLE PROGRAMto Active Program. Select the ADVANCED TAB (FIG. 79 ), the Start Timedisplays 0. Select INTERVALS TAB, the Time will show [10] and just aboveit, directly underneath STOP, NEXT SAMPLES: 9.8 minutes shows that thecounter is counting down (FIG. 80 ).

If a “Start Schedule” program will be run, the “Start Time” will beblank (FIG. 81 ). The Start Schedule setting is when a weekly or dailystart program is needed. A “Start Schedule” is the day and time theprogram to start running (Sampling). Press the “Start Schedule” buttonto access the numeric entry keys used to enter the day(s) in the areaunder “SETTINGS” (FIG. 82 ). Touch the days desired for the program totake samples and they will become active.

Enter the Hrs. and Min. in their respective box for the start time (FIG.83 ). Time entries use 24 hr clock but will be displayed in standard.For example, sampling Mon, Wed, Fri and starting at 7:00 a.m. (FIG. 84). After ensuring all selections are correct, press Save, and “UpdatedSuccessfully” will appear in the lower right-hand corner if the value isaccepted.

The Start on Float setting allows for an external float or switch toprovide the sampler with a run signal (FIGS. 85 and 86 ). Once this runsignal is received the program will run as scheduled until it iscompleted. This is a one-shot contact. For example, if monitoring the pHof a stream that must maintain 6.5 or above, the pH controller may beprogrammed to give an alarm (contact closure) when the pH falls belowthe 6.5. This contact then closes and makes the sampler run the programuntil it is complete. This also could be used as a float/contact start,once the contact closes the sampler runs the program.

Press the “Start On Float” button to access the input window under“SETTINGS”. If this setting is OFF the button will have the words OFF init (FIG. 85 ). If this setting is ON the button will have the word ON init (FIG. 86 ). After selecting ON/OFF, press Save, and “UpdatedSuccessfully” will appear in the lower right-hand corner if the value isaccepted (FIG. 87 ).

The Stop Time setting is the amount of time the sampler program is torun in minutes. The range is from 0 to 1440 minutes. Press the “StopTime” button to access the numeric entry keys used to enter the desiredamount of time in the window under “SETTINGS” (FIG. 88 ). Enter thedesired time values, press Save, and “Updated Successfully” will appearin the lower right-hand corner if the value is accepted.

The Stop schedule setting may be used when programing a “StartSchedule”. A “Stop Schedule” setting is the day and time the program isto stop running (sampling) (FIG. 89 ). For example, a programmed “Startschedule” may be scheduled for every Monday at 3:00 pm and to stop onTuesday at 7:00 am (FIG. 90 ). Press “Stop Schedule” button to accessthe numeric entry keys used to enter the stop time in the window under“SETTINGS”. Touch the days desired for the program to stop takingsamples and they will become active. Enter the Hrs. and Min. in theirrespective box for the start time. Time entries use 24 hr clock but willbe displayed in standard format. After entering the date(s) time(s),press Save, and “Updated Successfully” will appear in the lowerright-hand corner if the value is accepted (FIG. 91 ).

The Freeze On Float Off setting allows running samples based on waterlevels or pH levels, or any external contact input. When the externalcontact is closed, the scheduled program will run, when the contactopens, the program will stop. The program will resume every time thecontact is closed, or the program is complete, and the sampler shuts off(FIG. 92 ).

For example, a for stream that does not have running water all the time,it may be desirable to be able to sample the stream when there is waterpresent. Installation of a float will trigger based on a certain level.When that level is reached, the float will close a contact and triggerthe sampler to run its program. When the level of the water goes downand the float switch turns off, the sampler stops and when the levelrises again the float closes a contact and the sampler runs its programagain.

Press “Freeze On Float Off” button to access the numeric entry keys usedto select ON/OFF under “SETTINGS”. After selecting ON/OFF per yourpreference press Save, and “Updated Successfully” will appear in thelower right-hand corner if the value is accepted (FIG. 93 ).

The No Bottle Limit setting allows pulling as may samples as desired perbottle and cancelling out any number in the “Samples Per Bottle” program(FIG. 94 ). Press the “No Bottle Limit” button to access the windowunder “SETTINGS”. Select the desired setting ON or OFF. After selectingON/OFF press Save, and “Updated Successfully” will appear in the lowerright-hand corner if the value is accepted (FIG. 95 ).

The Auto Restart Schedule setting allows the scheduled programs to runcontinuously without being reset. By turning this setting ON, theschedule programs will automatically start/start without being manuallyreset. Select the desired setting ON or OFF (FIG. 96). After selectingON/OFF per your preference press Save, and “Updated Successfully” willappear in the lower right-hand corner if the value is accepted (FIG. 97).

Temperature Fault setting provides an alarm output if the Temperaturegets above a set level for a set period of time (FIG. 98 ).

When the “ADVANCED” programming is completed, all the selections canviewed and verified under the ADVANCED TAB on the Home screen (FIG. 99).

The sampler may include a program will be set up for time-basedsampling. It may be modified as desired for specific needs. At start upthe Home screen will be displayed (FIG. 100 ). This may be the screenfrom which all programs may be started and stopped, and all programsettings may be viewed under their respective setting TABS.

To set up a NEW Program, press the Configuration icon on the left of theHome screen and it will advance to the “EXISTING PROGRAMS” screen (FIG.101 ). Press the “NEW” program button to change to the keyboard displayand prompt to change (type in) the name of the new program (FIG. 102 ).After a new name is typed in the window (“weekly” for example) and the“SUBMIT” button is pressed, the “EXISTING PROGRAMS” screen is displayed(FIG. 103 ). On the “EXISTING PROGRAMS” screen the “new program created”banner will be displayed in the lower right corner and a button with thename of the new program “weekly” will be displayed next to the“Program1” button.

To begin building the new program, press the “weekly” program button andit will be highlighted to indicate it is active. From this screen youmay also ACTIVATE, RENAME, or DELETE (DEL) any program listed (FIG. 104). Pressing the “weekly” button allows access to and change of the foursettings of the program: SAMPLING, INTERVAL, BOTTLE, and ADVANCED. Theprocess is the same as changing or modifying an existing program, whichis described hereinabove.

The Deleting Programs setting allows the easy removal of an existing ornewly created program from the unit. By pressing the program button thatyou want to remove you will be prompted to select ACTIVATE, RENAME orDEL (FIG. 105 ). Press the “DEL” button and confirmation to delete theprogram with a popup or cancel will be displayed (FIG. 106 ). Pressconfirm to delete the program.

The Rename Program setting allows the easy renaming of a program (FIG.107 ). If the new program name was misspelled or a different name isdesired, select the desired button, press rename and correct/rename theprogram (FIG. 108 ). Press confirm to accept the changes.

To access the device settings (FIG. 109 ), press Device (FIG. 110 ). TheGeneral area allows setup of Date & Time and access the Refrigeratortemperature adjustment screens (FIG. 111 ). The General menu can beaccessed while the program is running. To update the Date & Time selectthe Date & Time button (FIG. 112 ). Once the Date & Time are entered,press Submit, and Saved Successfully will appear in the lower right-handcorner of the screen (FIG. 113 ). The Date & Time will show up at thetop of the screen.

The Refrigerator settings is to adjust the inside temperature of thecabinet (FIG. 114 ). Pressing A raises the temperature and v lowers thetemperature. Adjust the settings and press Submit to save. Values Savedwill appear in the bottom Right Hand side (FIG. 115 ). The number doesnot represent the cabinet temperature but is a reference number to useto set the temperature. The refrigerator setting can be accessed in theGeneral menu while a program is running.

The Security Code setting is used to prevent unauthorized personnel fromtampering with the program Settings menu (FIG. 116 ). If a SecurityCoder is desired, press Security Code, it will be highlighted, and thenumeric entry screen will appear. Enter the desired numeric code andpress Submit. Value Saved will appear in the lower right-hand corner(FIG. 117 ). Once set, this code will be required to be entered toaccess the Settings (FIG. 118 ).

The sample programs will continue to run or shut off according to theprogram, but Settings cannot be accessed until the security code isentered. If a Security Code is not used leave it blank. When a Securitycode is activated and have returned to the Home Screen, the securitycode is activated. Pressing the Configuration Icon will take you to aSecurity Code screen (FIG. 119 ). To enter the settings screens, enterthe Security Code that was entered previously. If a Security Code wasentered, but needs to be removed, enter the Security Code to accesssettings, press Device and Security Code. Enter 0000, This Code willremove an existing code and disable the Security Code.

Select Language to set the display language (FIG. 120 ).

The Factory Reset setting is used to clear all the Log files (FIG. 121). When you press Reset Device!, Reset Done will appear in the lowerright-hand corner (FIG. 122 ). The log files will be permanently removed(FIG. 123 ).

The Sampler ID setting displays a unique number based on the processorinside the apparatus (FIG. 124 ).

To start a program that is already programmed, press the Run button fromthe home screen (FIG. 125 ). Before pressing the Run Button, notice thatthe Program State is IDLE PROGRAM and that the Current activated Programis Program1. After pressing the Run button, notice that the ProgramState is AUTOMATIC PROGRAM (FIG. 126 ). Once the program is running, newbuttons will be displayed on the screen; STOP—Program stops running;PAUSE—The current program will pause; MANUAL—Pressing this button willmake the sampler pull a manual sample. This Manual Sample will becounted in the overall samples to be pulled in the program.

While the Home Screen has the Sampling Tab selected, the screen willdisplay in the upper right the Percentage (for example 2%) of samplescompleted (FIG. 127 ). Underneath the Stop Button the number of samplesthat have been pulled and a running total of the ml pulled will bedisplayed.

Pressing the Stop button will cause the program to display a Warning!message and ask for confirmation to Stop the program from running (FIG.128 ). This allows to Cancel or proceed by pressing Confirm! PressingConfirm will stop the current program and show why the program stoppedto the right of the RESET button. For example, “STOP CAUSE: user” (FIG.129 ).

When RESET is pressed, the Home screen is displayed (FIG. 130 ).

When the sampler is in the process of pulling a Sample, the Stop, Pauseand Manual buttons are not displayed, and a Cancel button is displayed(FIG. 131 ). The Cancel button allows cancellation of the current sampleat its current point in the sampling process. Once the sample processhas started, in the bottom right-hand side of the screen an indicatordisplays where the current program is at in its sampling process.

Pressing the PAUSE button will Pause the current running samplingprogram (FIG. 132 ). When the program goes into Pause, the PAUSE buttonchanges to the RESUME button. Pressing the RESUME button will start theprogram again.

When the sampling process is running, the current process is displayedin the bottom right of the screen (FIGS. 133 and 134 ). Once thePre-purge is completed the sampler will Draw Sample then Post-Purge.Once these have been completed, the sampler is draining the sample intothe bottle is displayed (FIG. 135 ) and then clean chamber is displayed(FIG. 136 ).

The Tabs (Sampling, Intervals, Bottle and Advance) are used for twodifferent purposes. The information above each tab shows the currentsampling status while in the Run mode and below the tab is how thesampler is programmed (see FIGS. 137-144 ).

The Archive files and Alerts can be accessed by touching the file iconor the red bell for alerts on the left side of the screen.

The Archive file collects data for each sample taken (FIG. 145 ).

The Alerts file shows data if there is an issue with a current sampleevent (FIG. 146 ).

It is to be understood that while certain now preferred forms of thisinvention have been illustrated and described, it is not limited theretoexcept insofar as such limitations are included in the following claims.Many different arrangements of the various components depicted, as wellas components not shown, are possible without departing from the scopeof the claims below. Embodiments of the technology have been describedwith the intent to be illustrative rather than restrictive. Alternativeembodiments will become apparent to readers of this disclosure after andbecause of reading it. Alternative means of implementing theaforementioned may be completed without departing from the scope of theclaims below. Certain features and sub-combinations are of utility andmay be employed without reference to other features and sub-combinationsand are contemplated within the scope of the claims.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:
 1. A method for wastewater samplingcomprising: radially positioning, by a controller, a first end of asample tube within a sample chamber to receive a wastewater samplevolume; directing, by the controller, a vacuum/pressure pump to initiatea vacuum cycle to pull a vacuum on the sample chamber to draw thewastewater sample into the sample chamber; and energizing, by thecontroller, the vacuum/pressure pump to pressurize the sample chamberupon receiving a predetermined oversample volume of the wastewatersample to force the oversample volume from the sample chamber.
 2. Themethod of claim 1 wherein said sample chamber includes an arcuate outerwall, and wherein the first end of said sampling tube remainsequidistant from an inner surface of the arcuate outer wall as thesampling tube rotates within the sample chamber.
 3. The method of claim1 further comprising energizing a pinch valve assembly including a drainline coupled to a drain of the sample chamber, by the controller toselectively drain the sample chamber.
 4. The method of claim 1 furthercomprising selectively energizing a refrigeration unit by the controllercoupled to maintain the wastewater sample at a predeterminedtemperature.
 5. The method of claim 1 further comprising a vacuumtermination means coupled to said system controller to preventcollection of excess wastewater in the sample chamber during the vacuumcycle.
 6. The method of claim 5 wherein the vacuum termination meanscomprises a sample balance coupled to the sample chamber for measuringthe weight of the sample chamber, the controller coupled to the samplebalance to receive an output therefrom to terminate the vacuum cycle andinitiate the pressure cycle.
 7. The method of claim 1 further comprisingenergizing the vacuum/pressure pump for a predetermined period of timefor a sample tube position for a sample size by the controller.
 8. Themethod of claim 1 further comprising energizing the vacuum/pressure pumpfor a measured flow rate for a sample size by the controller.
 9. Themethod of claim 1 wherein said system controller energizes saidvacuum/pressure pump for a combination flow rate and period of time fora predetermined sample size.